The present invention relates to a manufacturing method of a core for rotary electric machines which is composed of laminated magnetic steel sheets.
Among the conventional methods for manufacturing stator cores for rotary electric machines, there is a first method by which a cylindrical core is manufactured by punching out annular sheet cores by press work and laminating these sheet cores.
This first manufacturing method by which the annular sheet cores are punched out by the press work produces waste portions inside and outside of the sheet cores, thereby lowering yield.
A second manufacturing method, which improves the yield, is illustrated in FIGS. 20(a) through 20(d).
According to the second method, a core division sheet 1 which has an engaging concavity 1a and an engaging convexity 1b as shown in FIG. 20(a) is first punched out by press work. A core segment 2 is composed by laminating such core division sheets 1 as shown in FIG. 20(b), the engaging convexity 1b of the core segment 2 is positioned against one end of the engaging concavity 1a of an adjacent core segment 2 as shown in FIG. 20(c) and the convexity 1b is slid or inserted into the concavity 1a for coupling the core segments 2, thereby forming a cylindrical stator core 3, as shown in FIG. 20(d).
The second manufacturing method by which the divided core sheets 1 are punced out by the press work does not produce waste portions unlike the first manufacturing method and provides a favorable yield, but poses a problem that workability is low at the coupling stage shown in FIG. 20(c). Speaking of a measure to obtain a favorable stator core 3 by lowering magnetic reluctance, it is necessary to reduce clearance between the coupled core segments, including the concavity 1a and the engaging convexity 1b, so as to eliminate a play among the coupled core segments 2, but a smaller play will require higher dimensional precision for coupling the core segments 2.
Further, a stronger inserting force is required at a stage to engage a starting end of the engaging concavity with one end of the engaging convexity and slide the core segment 2 since the engaging convexity is inserted while causing friction not only between the engaging concavity 1a and the engaging convexity 1b but also over the entire joined surfaces including those of the engaging concavity and the engaging convexity.
A primary object of the present invention is to provide a stator core which allows core segments to be coupled with high workability and has favorable magnetic characteristics even when the stator core is manufactured by punching out core division sheets by press working and coupling core segments formed by laminating the divided core sheets so as to obtain a favorable blanking yield.
A method of manufacturing a core for rotary electric machines according to the present invention is configured to compose serial core segment assembly by coupling a plurality of core segments which are composed of laminated core division sheets, and then form a cylindrical core by bringing both ends of the serial core segment assembly into contact with each other so as to bend it into an annular form.
According to the present invention, it is possible to obtain a stator core which assures a high blanking yield, high workability for core segment coupling and favorable magnetic characteristics.
A method of manufacturing a core for rotary electric machines, according to a first aspect of the present invention, includes forming a plurality of core segments by laminating core division sheets on which tees are formed, forming a serial core segment assembly by coupling adjacent core segments with one another, bend the serial core segment assembly into an annular form so that yokes of all the adjacent core segments are brought into contact with one another and bringing yokes of core segments located at both ends of the serial core segment assembly into contact with each other, thereby forming a magnetic circuit.
A method of manufacturing a core for rotary electric machines, according to a second aspect of the present invention, includes coupling adjacent core segments with each other at a location which will form an outer circumference when the magnetic circuit is formed by bending the serial core segment assembly into the annular form at the stage to compose the serial core segment assembly by coupling the adjacent core segments with one another.
A method of manufacturing a core for rotary electric machine, according to a third aspect of the present invention, includes fixing both the ends of the serial core segment assembly by welding or cementing them to each other after the magnetic circuit is formed by bending the serial core segment assembly into the annular form and bringing the yokes at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machine, in accordance with a fourth aspect of the present invention, includes coupling both the ends of the serial core segment assembly with each other using a coupling device after the magnetic circuit is formed by bending the serial core segment assembly into the annular form and bringing the yokes of the core segments located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to a fifth aspect of the present invention, includes laminating core division sheets on which tees are formed, molding resin on surfaces of the core segments except end surfaces of yokes thereof, forming a serial core segment assembly by coupling adjacent core segments with one another, bend the serial core segment assembly into an annular form so that yokes of all adjacent core segments are brought into contact with one another, bring yokes of core segments located at both the ends of the serial core segment assembly into contact with each other for forming a magnetic circuit and coupling both the ends of the serial core segment assembly by welding the molded material at both the ends of the serial core segment assembly.
A method of manufacturing a core for rotary electric machine, according to a sixth aspect of the present invention, includes forming a plurality of core segments by laminating core division sheets on which tees are formed, forming a serial core segment assembly by coupling adjacent core segments with one another, molding resin on the surfaces of the serial core segment assembly except end surfaces of yokes of the core segments, bending the serial core segment assembly into an annular form so that yokes of all the adjacent core segments are brought into contact with one another, forming a magnetic circuit by bringing yokes of core segments located at both the ends of the serial core segment assembly into contact with each other and couple both the ends of the serial core segment assembly with each other by welding the molded material at both the ends of the serial core segment assembly.
A method of manufacturing a core for rotary electric machines, according to a seventh aspect of the present invention, includes forming a plurality of core segments by laminating core division sheets on which tees are formed, forming a serial core segment assembly by coupling adjacent core segments with one another, bending the serial core segment assembly into an annular form so that yokes of all adjacent core segments are brought into contact with one another, forming a magnetic circuit by bringing yokes of the core segments disposed at both ends of the serial core segment assembly into contact with each other and couple both the ends of the serial core segment assembly with each other by molding resin on the serial core segment assembly bent in the annular form.
A method of manufacturing a core for rotary electric machines, according to an eighth aspect of the present invention, includes coupling both the ends of the serial core segment assembly with each other by engaging a first engaging portion formed at one end of the serial core segment assembly with a second engaging portion formed at the other end of the serial core segment assembly after the magnetic circuit is formed by bending the serial core segment assembly into the annular form and bringing the yokes of the core segments located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to a ninth aspect of the present invention, includes coupling both the ends of the serial core segment assembly by overlapping and engaging first and second engaging portions in a radial direction of the serial core segment assembly bent in the annular form.
A method of manufacturing a core for rotary electric machines, according to a tenth aspect of the present invention, includes coupling both the ends of the serial core segment assembly by overlapping and engaging the first and second engaging portions laminated in the laminated direction of the core division sheets.
A core for rotary electric machines according to an eleventh aspect of the present invention comprises a core for rotary electric machines whose magnetic circuit is formed by forming a plurality of core segments of laminated core division sheets having tees formed thereon, coupling the core segments with one another so as to form a serial core segment assembly, bending the serial core segment assembly into an annular form so that yokes of all adjacent core segments are brought into contact with one another and bringing yokes of core segments located at both ends of the serial core segment assembly into contact with each other, characterized in that coupling portions for coupling adjacent core segments with one another are disposed over the entire region in the laminated direction of the core segments.
A core for rotary electric machines, according a twelfth aspect of the present invention comprises a core for rotary electric machines whose magnetic circuit is formed by forming a plurality of core segments of laminated core division sheets having tees formed thereon, coupling the core segments with one another so as to form a serial core segment assembly, bending the serial core segment assembly into an annular form so that yokes of all adjacent core segments are brought into contact with one another and bringing yokes of core segments located at both ends of the serial core segment assembly into contact with each other, characterized in that coupling portions for coupling the adjacent core segments to one another are formed in a partial region in the laminated direction of the core division sheets.
A core for rotary electric machines according to a thirteenth aspect of the present invention, comprises a core, having a concavity formed on an end surface of the yoke of the core segment over the entire region in the laminated direction of the core division sheets as coupling portions for coupling adjacent core segments with one another and a convexity is formed on the other end surface of the yoke of the core segment at a location corresponding to the concavity over a partial region in the laminated direction of the core division sheets.
A method of manufacturing a core for rotary electric machines, according to a fourteenth aspect of the present invention, includes engaging a coupling convexity which is formed on one of adjacent core segments and has an arc-like tip in a planar shape with the other core segment rotatably over 180 degrees so that an arm connecting a root to a tip of the coupling convexity of the core segment will not be plastically deformed at the stages to compose the serial core segment assembly by engaging the coupling convexity formed on the core segment with the other core segment, and to form the magnetic circuit by bending the serial core segment assembly into the annular form and bringing the yokes of the core segment located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to a fifteenth aspect of the present invention, includes engaging a coupling convexity which is formed on one of adjacent core segments and has an arc-like tip in a planar shape with the other core segment rotatably within a defined range over 180 degrees and allow an arm connecting a root to the tip of the coupling convexity of the core segment to be plastically deformed in the course of the bending of the serial core segment assembly into the annular form at the stages to compose the serial core segment assembly by engaging the coupling convexity on one of adjacent core segments with the other core segment, and to form the magnetic circuit by bending the serial core segment assembly into the annular form and bringing the yokes of the core segments located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to a sixteenth aspect of the present invention, includes allowing an arm connecting a root to a tip of the coupling convexity to be plastically deformed while the coupling convexity formed on one of adjacent core segments is fitted into the other core segment and the serial core segment assembly is bent into the annular form at the stages to compose the serial core segment assembly by engaging the coupling convexity formed on one of adjacent core segments with the other core segment, and to form the magnetic circuit by bending the serial core segment assembly into the annular form and bringing the yokes of the core segments located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to a seventeenth aspect of the present invention, includes pressing or inserting the coupling convexity toward depth of the coupling concavity while the arc-shaped tip of the coupling convexity formed on one of the adjacent core segments is engaged with the arc-shaped coupling concavity formed in the other core segment and the serial core segment assembly is bent into the annular form at the stages to compose the serial core segment assembly by engaging the coupling convexity formed on one of the adjacent core segments with the other core segment, and forming the magnetic circuit by bending the serial core segment assembly into the annular form and bringing the yokes of the core segments located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to an eighteenth aspect of the present invention, includes coupling adjacent core segments with each other by using a coupling pin and allowing the coupling pin to be deformed for bending the serial core segment assembly into the annular form at the stages to compose the serial core segment assembly by engaging the coupling convexity formed on one of adjacent core segments with the other core segment, and forming the magnetic circuit by bending the serial core segment assembly into the annular form and bringing the yokes of the core segments located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to a nineteenth aspect of the present invention, includes using a coupling pin as the coupling device.
A method of manufacturing a core for rotary electric machines, according to a twentieth aspect of the present invention, includes continuously winding a wire in series around a plurality of tees of the serial core segment assembly and form a magnetic circuit by bending the serial core segment assembly having the continuous windings into an annular form.
A method of manufacturing a core for rotary electric machines, according to a twenty-first aspect of the present invention, includes fixing by welding portions which are to form outer circumferences of the coupling portions of the serial core segment assembly after the magnetic circuit is composed by bending the serial core segment assembly into the annular form and bringing the yokes of the core segments located at both the ends of the serial core segment assembly into contact with each other.
A method of manufacturing a core for rotary electric machines, according to a twenty-second aspect of the present invention, includes forming a plurality of core segments by laminating core division sheets on which tees are formed, forming a serial core segment assembly by coupling adjacent core segments with one another, mounting an insulator made of resin on each core segment of the serial core segment assembly, bending the serial core segment assembly into an annular form so that yokes of all adjacent core segments are brought into contact with one another, forming a magnetic circuit by bringing yokes of core segments located at both ends of the serial core segment assembly into contact with each other, and coupling both the ends of the serial core segment assembly by welding the insulators located at both the ends of the serial core segment assembly.
A method of manufacturing a core for rotary electric machines, according to a twenty-third aspect of the present invention, includes forcibly expanding a concavity which is formed at one end of the serial core segment assembly and couple both ends of the serial core segment assembly by applying a pressure to outside the forcibly expanded concavity after a convexity formed on the other end of the serial core segment assembly is inserted into the forcibly expanded concavity in a radial direction of the serial core segment assembly bent in the annular form.